The present invention relates to a solid-state imaging device, and more specifically to a solid-state imaging device of a package construction having reduced external sizes.
FIGS. 1A and 1B are a plan view and a sectional view of a conventional solid-state imaging device, in which a package 1 made of a ceramic material or the like has in a central portion thereof a recessed portion 1c for accommodating a solid-state imaging element, the recessed portion being defined by a stepped portion 1a and a bottom portion 1b. Bonding pads 2 are applied on the predetermined positions of the stepped portion 1a. Bonding pads 2 are connected to electrically conductive metal patterns 3 that are formed in the package 1, and are further connected to lead terminals 4 for connection to external units, that are arrayed on the side surfaces of the package 1. Further, a light-receiving element 5 is adhered onto the bottom portion 1b in the recessed portion 1c of the package 1 with a light-receiving portion 5a being directed toward the front. Bonding pads 5b formed on the light-receiving element 5 are connected via bonding wires 6 to the bonding pads 2 that are formed on the stepped portion 1a of the package 1. Further, shift registers 5c are formed around the periphery of the light-receiving element 5 to drive the light-receiving portion 5a. In order to prevent the light-receiving element 5 from being deteriorated, the open end or the front side of the package 1 is air-tightly sealed with a transparent glass plate 8 via a sealing agent 7. Shift registers 5c consist of integrated circuits of a complicated circuit construction as shown in FIG. 2. In practice, therefore, it is very difficult to change the arrangement of the light-receiving portion 5a and the shift registers 5c in the light-receiving element having a small area. Accordingly, the relation in position between the light-receiving portion 5a and the shift registers 5c has been standardized as shown in FIG. 1A. A distance l has also been specified between the edge of the light-receiving element 5 and the stepped portion 1a. According to the conventional imaging device which is illustrated more clearly in FIG. 1B, a center axis C.sub.1 of the light-receiving element 5 is brought into agreement with a center axis C.sub.2 of the recessed portion 1c (which also is a center axis of the package 1 or the imaging device), and a center axis C.sub.3 of the light-receiving portion 5a is deviated by a distance d from the center axis C.sub.2 of the recessed portion 1c or from the center axis C.sub.1 of the light-receiving element 5. In this case, furthermore, the transparent glass plate 8 is centered with the center axis C.sub.1 of the light-receiving element 5 in a symmetrical manner in the upper and lower directions and in the right and left directions.
With thus constructed solid-state imaging device, however, since the center axis C.sub.3 of the light-receiving portion 5a of the light-receiving element 5 is not in agreement with the center axis C.sub.2 of the recessed portion 1c, i.e., since the center axis C.sub.3 is deviated by a distance d from the center axis C.sub.2, it is necessary to employ the transparent glass plate 8 having an area which is greater than the area of an aperture required for covering the incident angle .theta. of light. Consequently, the outer size of the package 1 tends to be inevitably increased. Furthermore, when the solid-state imaging element is to be mounted on a camera, the center axis of the lens of the camera must be brought into agreement with the center axis of the light-receiving portion of the element. For this purpose, the package must be offset inevitably by a distance d relative to the lens of the camera.